Method for measurement report event operation and network signaling in UE autonomous handover

Abstract

The present disclosure relates to a communication technique for fusing, with an IoT technology, a 5G communication system for supporting a higher data transfer rate than a 4G system, and a system therefor. The present disclosure may be applied to intelligent services, such as smart homes, smart buildings, smart cities, smart cars or connected cars, health care, digital education, retailing, security and safety-related services, etc. on the basis of 5G communication technologies and IoT-related technologies. Disclosed in the disclosure is a method for measurement report/event operation and network signaling in an UE autonomous handover.

What is claimed is: 
     
       1. A method performed by a terminal in a wireless communication system, the method comprising:
 receiving, from a serving base station of a source cell, a first message for conditional handover configuration, the first message comprising first information on at least one candidate target cell and second information on at least one execution condition for a conditional handover; 
 in case that a radio link failure (RLF) for the source cell occurs, staying in a radio resource control (RRC) connected state and identifying a valid candidate cell; and 
 in case that the valid candidate cell is one of the at least one candidate target cell, transmitting, to a target base station of the valid candidate cell, a second message for the conditional handover based on the first information, wherein an RRC re-establishment procedure is not performed. 
 
     
     
       2. The method of  claim 1 , further comprising in case that the valid candidate cell is not any of the at least one candidate target cell, performing the RRC re-establishment procedure after the RLF for the source cell occurs. 
     
     
       3. The method of  claim 1 , wherein the transmitting of the second message for the conditional handover further comprises applying a corresponding configuration for the valid candidate cell included in the first information. 
     
     
       4. The method of  claim 1 , wherein the first information on the at least one candidate target cell includes identifier (ID) information of the at least one candidate target cell. 
     
     
       5. The method of  claim 1 , wherein the second information on the at least one execution condition for the conditional handover includes measurement ID information. 
     
     
       6. A terminal in a wireless communication system, the terminal comprising:
 a transceiver; and 
 a controller configured to:
 receive, from a serving base station of a source cell via the transceiver, a first message for conditional handover configuration, the first message comprising first information on at least one candidate target cell and second information on at least one execution condition for a conditional handover, 
 in case that a radio link failure (RLF) for the source cell occurs, stay in a radio resource control (RRC) connected state and identify a valid candidate cell, and 
 in case that the valid candidate cell is one of the at least one candidate target cell, transmit, to a target base station of the valid candidate cell via the transceiver, a second message for the conditional handover based on the first information, wherein an RRC re-establishment procedure is not performed. 
 
 
     
     
       7. The terminal of  claim 6 , wherein the controller is further configured to in case that the valid candidate cell is not any of the at least one candidate target cell, perform the RRC re-establishment procedure after the RLF for the source cell occurs. 
     
     
       8. The terminal of  claim 6 , wherein, to transmit the second message for the conditional handover, the controller is further configured to apply a corresponding configuration for the valid candidate cell included in the first information. 
     
     
       9. The terminal of  claim 6 , wherein the first information on the at least one candidate target cell includes identifier (ID) information of the at least one candidate target cell. 
     
     
       10. The terminal of  claim 6 , wherein the second information on the at least one execution condition for the conditional handover includes measurement ID information.